Actually i have bought some article how i can confirm this article is unique and never posted any other site.?

[Rafikuzzaman]

[Mat]

Easiest way is just grab a bit of the text from the article and google it, you will soon see if it is unique or not. alternatively use copyscape.

[Roy Pierce]

Copy out your whole article and past it on articles checker sites they find and higlighted all the lines which are matched from any others sites
http://smallseotools.com/

[Ruth]

You can check your content on site plagiarisma.net.You should have membership of that site.But this site is really useful for content or articles writers

[Vincent]

Do follow this link: smallseotools.com/plagiarism-checker/

When the test is done, you’ll also be given an exact percentage that tells you how original or unique your article is.